A tiny fossil preserved in red sandstone from Scotland has been identified as the oldest known insect.

The fossil suggests insects were among the earliest animals to live on land and that winged flight may have emerged earlier than previously thought.

The fragmentary specimen from Rhynie in Aberdeenshire comes from deposits dated to between 396 and 407 million years old, during the Devonian Period.

Details of the discovery are published in the scientific journal Nature.

The discovery suggests that insects almost certainly evolved in the Silurian Period, some 438-408 million years ago.

"In the late Silurian is where we have the first evidence for terrestrial ecosystems, so it really says that insects were represented in the earliest ecosystems on land," co-author Michael Engel of the University of Kansas, US, told BBC News Online.

Anatomical characteristics of the fossil's jaw identify it as a true insect, Dr Engel and co-author David Grimaldi write in Nature.